Multilayer microfluidic device

Abstract

The present invention provides microfluidic devices constructed from four layers. The layers include a rigid substrate layer, a patterned rigid layer having thickness t, a patterned elastomeric layer having thickness greater than t, and a rigid support layer. Microfluidic structures in the devices are defined by the alignment of openings in the patterned rigid layer and the patterned elastomeric layer. The rigid support layer, rigid substrate layer, and patterned rigid layer may be made of any rigid material, including but not limited to plastic or silicon-containing materials, such as glass, quartz, or SiO 2 -coated materials. Similarly, the patterned elastomeric layer may be made of any elastomeric material, including but not limited to polydimethylsiloxanes, polymethylmethacrylates, perfluoropolyethers, or combinations thereof. Microfluidic devices according to the present invention may include sensors or sensor arrays. The microfluidic devices are fabricated using the provided error-tolerant alignment, biocompatible process.

1. A microfluidic device, comprising:
 a) a rigid substrate layer, wherein said rigid substrate layer has a first surface and a second surface; 
 b) a patterned rigid layer having thickness t, wherein said patterned rigid layer has a first surface and a second surface, wherein said first surface of said patterned rigid layer is bonded to said second surface of said substrate layer, and wherein said patterned rigid layer contains an opening that extends from said first surface to said second surface of said patterned rigid layer; 
 c) a patterned elastomeric layer having thickness greater than t, wherein said patterned elastomeric layer has a first surface and a second surface, wherein said first surface of said patterned elastomeric layer is bonded to said second surface of said patterned rigid layer, wherein said patterned elastomeric layer contains at least one opening that extends from said first surface to said second surface of said patterned elastomeric layer, and wherein said at least one opening in said patterned elastomeric layer and said opening in said patterned rigid layer are partially aligned; and 
 d) a rigid support layer, wherein said rigid support layer has a first surface and a second surface, and wherein said first surface of said rigid support layer is bonded to said second surface of said patterned elastomeric layer, 
 wherein said opening in said patterned rigid layer forms a microfluidic channel, wherein the walls of said microfluidic channel comprises at least three of said layers of said microfluidic device. 
 
     
     
       2. The microfluidic device as set forth in  claim 1 , wherein thickness t is between about 50 nm and about 5 μm. 
     
     
       3. The microfluidic device as set forth in  claim 1 , wherein the thickness of said patterned elastomeric layer is between about 1 μm and about 100 μm. 
     
     
       4. The microfluidic device as set forth in  claim 1 , wherein said at least one opening in said patterned elastomeric layer has a height that is between a fraction of the width of said opening to about two times the width of said opening. 
     
     
       5. The microfluidic device as set forth in  claim 1 , wherein said rigid support layer comprises glass, silicon, or plastic. 
     
     
       6. The microfluidic device as set forth in  claim 1 , wherein said rigid substrate layer comprises quartz, glass, or a SiO 2  coated substrate. 
     
     
       7. The microfluidic device as set forth in  claim 1 , wherein said patterned rigid layer comprises a silicon-based material. 
     
     
       8. The microfluidic device as set forth in  claim 1 , wherein said patterned elastomeric layer comprises at least one of polydimethylsiloxanes, polymethylmethacrylates, or perfluoropolyethers. 
     
     
       9. The microfluidic device as set forth in  claim 1 , wherein said rigid support layer has a partial cut starting from said second surface of said rigid support layer and extending from about 10% to about 90% into said rigid support layer, and wherein said partial cut is for unsealing said microfluidic device. 
     
     
       10. The microfluidic device as set forth in  claim 1 , further comprising a sensor array situated on said rigid substrate layer, wherein said sensor array is fluidically connected to said microfluidic channel, wherein said sensor array comprises a plurality of high aspect ratio sensors, wherein each of said plurality of sensors is split into a plurality of segments, and wherein said plurality of segments are connected in series, in parallel, or in any combination thereof. 
     
     
       11. The microfluidic device as set forth in  claim 10 , wherein said sensor array is a magnetic sensor array or a magnetoresistive sensor array, and wherein one of said plurality of sensors has a high aspect ratio or an effective aspect ratio greater than about 1000. 
     
     
       12. The microfluidic device as set forth in  claim 11 , wherein one or more biomolecular or chemical probes is immobilized to each of said plurality of sensors. 
     
     
       13. The microfluidic device as set forth in  claim 12 , wherein the same or different biomolecular or chemical probes are immobilized to each of said plurality of sensors, and wherein segments containing one of said biomolecular or chemical probes are interspersed spatially with segments containing another of said biomolecular or chemical probes. 
     
     
       14. The microfluidic device as set forth in  claim 1 , wherein said patterned elastomeric layer is not uniform in thickness. 
     
     
       15. The microfluidic device as set forth in  claim 1 , wherein said patterned rigid layer is not uniform in thickness.